With modern engines there is an increasing demand that the initial flow of fuel to the engine should be at a controlled rate and in order to achieve this the initial movement of the valve member away from the seating is carefully controlled. In one arrangement the clearance between the valve member and the seating forms a restrictor which restricts the flow of fuel through the outlet orifice. In another arrangement the orifice can extend from immediately downstream of the seating so that the tip of the valve member provides controlled obturation of the inner end of the orifice. With injectors of the types described above it is important to ensure that the valve member remains concentric with the seating as it moves away from the seating.